Rajendar started off in the Kollywood industry making successful films which included him as an actor, playback singer, dancer and scriptwriter. He normally serves as, but not limited to director, actor, songwriter, art director,production manager, playback singer. During the 1980s all his movies were blockbusters running for years and the songs were also well appreciated. He is known for introducing new faces in his movies, and many of the actresses who debuted in his movies have been successful in South Cinema, including Amala, Nalini, Jyothi, Jeevitha, and Mumtaj. He has composed musics over 35 films and also as a lyricist for his own composition. Rajendar also distributes films under his home banner 'Simbu cine arts'. His latest film distribution, as of mid-2011 is his son Silambarasan's film Vaanam which will be distributed in the Chennai and Madurai region. He started his party All India Latchiya Dravida Munnetra Kazhagam in April 2004. The party was formed as a result of T. Rajendar's expulsion from Dravida Munnetra Kazhagam.Before expulsion he was the propaganda secretary of DMK and was elected from Park Town constituency during 1996 Assembly polls.He further supported the AIADMK in the 2006 Assembly elections. After 2006 elections, DMK came back to power and he was made vice-chairman, Small Savings Scheme. He, subsequently, quit the post. He diversified his role as Director, actor, songwriter, screenwriter, Musician, producer, cinematographer, playback singer, politician, film distributor.